Use the prepositions below to complete the sentences which follow. at, for, in (x2), of (x2), with

The trees in the forest are .... least three hundred years old. There's no such product ............... the market as far as I know. What was your reason ............... resigning from the company? + They've replaced workers. .... computer-controlled machines in nearly all their factories. There's been an increase ... the number of people moving abroad to get a better job. You can't go in unless you're dressed ............... formal clothes. ! It was a lack .... ........... rain that caused the crop failure. He survived as a result ............ the surgeon's great skill.​